Suspension for a 135kg velomobile

Question

I'm designing a four-wheel velomobile as a small city bike with good weather protection. The top speed in the city is about 25km/h (7m/s).
The total weight of the velomobile is 35-45kg, and I expect the rider with some luggage to be 65kg to 100kg. So the total weight is 100 to 150kg.
The weight distribution is 40/60, where most of the weight is on the back wheels. The velomobile is to be front-drive, and it adds complexity in the design but should not affect the suspension.
The small bumps that make the person bouncing about and make them uncomfortable are 0,5cm to 3cm in the city. It should be a firm but smooth ride on cobble roads and across potholes.
How do I design and calculate the suspension to make it good? The suspension design is double wishbone. Yes, I could (and would like to) make adjustments when changing from a 65kg rider to a 100kg rider, but how do I calculate the proper settings?

I've seen this answer - but I did not quite understand if that also works for very light loads: Car Suspension Force Equations

Tiger Guy · Answer

How do I design and calculate the suspension to make it good?

This is quite an ask.  This is frankly beyond the capability of a degreed Mechanical Engineer without some specialist training.  Sure, I'd know where to start but I'd never take on such a thing by myself.  You're talking about design of the linkages plus the appropriate spring and damper rates.  So I guess you probably need to start with Statics, Dynamics, Machine Design, and Vibrations as starter courses (Vibrations has some serious math pre-requisites).
What I would do is go look at similar products and see how they do it.  You'd probably have better luck with someone who fabs bikes for a living than an engineer, unless the engineer did this type of work already.

Suspension for a 135kg velomobile

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